The enzymatic degradation of collagen is felt to play a major role in the crippling joint destruction seen in patients with rheumatoid arthritis and the collagenase derived from rheumatoid synovial cells has been incriminated in this process. The neutrophil is a circulating cell which accumulates at sites of inflammation including rheumatoid synovial cells has been incriminated in this process. The neutrophil is a circulating cell which accumulates at sites of inflammation including rheumatoid synovial fluid. This cell possesses at least three collagenolytic enzymes: an interstitial collagenase which degrades types I, II, and III collagens; elastase which degrades types III and IV collagens; and a gelatinase which degrades native type V collagen as well as denatured collagens. The relative contribution of these enzymes in the rheumatoid process in unknown. The first objective of this proposal is the purification and characterization of the interstitial collagenase and the gelatinase of the human neutrophil. This will be accomplished using standard chromatographic techniques with the additional aid of monoclonal antibodies. The active and latent forms of these enzymes will be characterized with particular focus on the changes which occur during activation. A panel of monoclonal antibodies will be raised against these enzymes for the following purposes: 1) as an aid in the purification and characterization of the enzymes; 2) to determine the relationship between certain enzyme function such as substrate binding and actual substrate cleavage and; and 3) as specific probes for the detection of the enzymes in synovial fluid. This latter objective will include the development of specific immunoassays which will specifically recognize the collagenases derived from neutrophils. These assays will be used to quantitate these collagenases in rheumatoid synovial fluid. The substance(s) present in rheumatoid synovial fluid which are capable of activating the latent forms of these enzymes will be purified using standard chromatographic techniques. These substances will be characterized with regard to their molecular structure and proteolytic activity.